Watching Doc Rivers on the sideline during Celtics games is worth the price of admission. He stomps around after questionable calls, smiles sarcastically after a ticky-tack foul, and places his hands, fingers spread, above his head in disbelief when he completely disagrees with an official’s decision.

Wednesday night in Toronto, Rivers was especially annoyed with the officiating at Air Canada Centre, especially the calls of Brent Barnaky. Barnaky is in his third season as an NBA official and, at 37, is one of the youngest in the league.

Before becoming an official, Barnaky was a civil trial lawyer, so he doesn’t lose many arguments; he still works as a pro bono lawyer in the offseason.

After the Raptors attempted 10 free throws in the first quarter and the Celtics none, Rivers became enraged and came close to being ejected from what became his 400th win as Celtics coach. He picked up a technical foul for arguing with Barnaky during a Celtics possession, costing his team a chance to score and handing the Raptors a free throw.

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With his status for the rest of the game hinging on a couple more choice words, Rivers was approached by Avery Bradley. The 22-year-old point guard walked over to his coach and instructed him to sit down and chill out.

Rivers cooperated, walking back to the bench and sitting quietly for the rest of the half. Usually, it is Rajon Rondo, Kevin Garnett, or Paul Pierce who controls Rivers during tirades, or assistant coach Armond Hill will set his best screen to block Rivers from approaching an official.

This time, the responsibility was left to Bradley, all of 113 NBA games into his career, to control a coach almost 30 years his senior. And the coach didn’t utter a word of protest.

Bradley’s early NBA career has been affected by injuries, but perhaps it was a signature moment of his growing leadership.

“It’s the same thing that he would do for us,” Bradley said. “At the end of the day, he’s like a player to us. We’ve just got to all stick together and he was a little frustrated. You just have to keep him in it. We needed him just like he needed us.”

Bradley is correct, Rivers is like a player. He takes a player’s mentality into every game. But he also uses his savvy and polish from 14 years of coaching to work the officials. He also has no issue listening to his players, especially Garnett and Pierce, who also have given him the “c’mon, Doc” nudge back to the bench.

Bradley doing that is a
surprise, but also an indication that the trust in him is spreading, especially from Rivers, who has an infamous distaste for putting his faith in younger players. Rivers was forced to trust Rondo in 2007 because Rondo was the best point guard on the team.

Rivers’s relationship with and confidence in Bradley have grown over the past few years. He assured doubters two years ago that Bradley could play — that he could shoot and was more than just a defender. It took a couple of years for his words to ring true, but they did.

Rivers may not have taken orders from Fab Melo, or even Brandon Bass, but with Bradley, he had no issue.

“You thought I was close [to being ejected]?” Rivers asked sarcastically. “So did my all my players. It was great. All of them at halftime [were] like, ‘Coach, I got you tonight.’

“But that was nice. Players sense the same thing I sense the other way with them. It’s always good. We as a team have a pretty good, open relationship. That was great with Avery. You need that.”

Bradley’s status is growing as his contributions to the team’s success without Rondo continue.

Bradley is a shy kid from Tacoma, Wash., but one whose confidence cannot be understated. With the Seattle lineage of NBA players, Bradley said he has played against professionals since middle school.

After the Celtics’ recent win over the Clippers, in which he drew a key charge on Jamal Crawford, who attended Seattle’s Rainier Beach High School, Bradley said he first faced Crawford in pickup games when Crawford was with the Chicago Bulls and Bradley had not yet reached high school.

Now Bradley has taken that swagger gained from being schooled by more experienced players during his prep days to the NBA.

And when Bradley likely saved his coach from getting booted from that 400th win, it stood as a significant moment in the growth of the player, who finally has made it into that circle of trust.

“It shows that I guess you can see the relationship me and Doc have now, the communication we use with each other,” said Bradley. “We always talk, and even like during the game, I might call a play and he might just go with the play I called.

“We feel more comfortable with each other. I’ve been here for three years. It shows how much I’ve grown, the leadership, maturity. I’ve improved so much as a player and as a person on and off the court because of my teammates and Doc.”

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